MEA 3013

What type of energy transformation occurs in the production of electricity by a hydroelectric dam?

• chemical energy to heat energy

• mechanical energy to electrical energy

• electrical energy to mechanical energy

• heat energy to chemical energy

During a solar eclipse, what object blocks the Sun?

• an asteroid

• a comet

• Earth

• the Moon

Which factor at the North and South poles makes the climate at the poles colder than the climate at the equator?

• the presence of oceans

• the lack of direct sunlight

• the presence of ice caps

• the lack of vegetation

How do the differences in bill shape help these birds survive in the same region?

• Each bill attracts a different type of predator.

• Each bill is best for eating a different kind of food.

• The bills are passed on randomly to the bird's offspring.

• The bills allow the birds to remove pests from their bodies.

A student has ham, fruit, bread, and juice for breakfast. Which food required the most energy per gram to be produced in the ecosystem?

• ham

• fruit

• bread

• juice

The graph below shows the estimated global population from AD 1 to AD 2000. Based on this trend, which statement is the best prediction of the competition for and cost of scarce natural resources in the future?

• Competition and cost of natural resources will both decrease.

• Competition and cost of natural resources will both increase.

• Competition for natural resources will increase, and cost of natural resources will decrease.

• Competition for natural resources will decrease, and cost of natural resources will increase.

The diagram below shows a copper wire loop situated near a bar magnet. What needs to be connected to the insulated wire to complete the circuit and to make the copper wire loop rotate?

• a battery

• a lightbulb

• a digital meter

• an electromagnet

Which organisms are most similar to pine trees because of how their food is obtained?

• algae

• honeybees

• mushrooms

• sea urchins

What does N most likely represent in the student's drawing?

• age

• weight

• amount of cytoplasm

• amount of genetic material

If 100 g of mercury (Hg) melts at -36°C, what is the melting point of 50 g of mercury?

• -9°C

• -18°C

• -36°C

• -72°C